Method of labelling soya varieties

ABSTRACT

The present invention is directed to a method which enables the user to select a suitable soya variety as a subsequent crop to maize when weed control in that maize crop has been carried out using HPPD inhibitor herbicides in a manner that “carry-over” damage to the soya crop is thereby avoided. The method includes the step of first selecting a “reference soya” that exhibits a visually determinable phytotoxicity with respect to the HPPD inhibitor herbicide used to carry out weed control on the maize crop. Next, the phytotoxicity of various soya varieties is determined in relation to the reference soya variety in the form of a factor. This factor can be expressed, for example, in letters, numbers, symbols, colors or other visual or acoustic signals or in words. These soya varieties are then labeled with the factor and can be made accessible to the user. For example, the factor can be indicated on or inside the product packaging or in an accompanying leaflet.

This application claims the benefit of U.S. Provisional Application No. 60/566,251, filed Apr. 29, 2004, now abandoned.

The present invention relates to a method of labeling soya varieties (Glycine max) as to their suitability as a subsequent crop to maize.

In the cultivation of crop plants, especially on a commercial scale, correct crop rotation is crucially important for yield stability (the achievement of high yields of good quality over a long period) and for the economic success of an agronomic business. For example, across large areas of the main maize-growing regions of the USA (the “central corn belt”), soya is grown as the subsequent crop to maize in over 75% of cases. Selective weed control in maize crops is increasingly being carried out using HPPD inhibitor herbicides. Although that class of herbicides has excellent suitability for that purpose, it can result in agronomically unacceptable phytotoxic damage to the crop plants in subsequent crops, especially in subsequent soya crops, because certain soya varieties are sensitive to even very small residues of such HPPD inhibitor herbicides (“carry-over” damage).

When a user, having used HPPD inhibitor herbicides in a maize crop, chooses soya as the subsequent crop, he currently has no satisfactory way of determining simply and with sufficient exactness from the several thousand commercially available varieties the suitability of a certain soya variety for growing as a subsequent crop to maize and thus of avoiding agronomically unacceptable phytotoxic damage to the soya crop. It is therefore the aim of the present invention to provide a method which enables the user to select, in a simple manner, a suitable soya variety as a subsequent crop to maize when weed control in that maize crop has been carried out using HPPD inhibitor herbicides, in order that “carry-over” damage to the soya crop is thereby avoided. That aim is achieved by the provision of the method according to the invention.

The method according to the invention for the labeling of soya varieties as to their suitability as a subsequent crop to maize when weed control in that maize crop has been carried out using HPPD inhibitor herbicides is as follows:

-   a) in a first step, a reference soya variety is selected which, when     grown as a subsequent crop to maize wherein weed control has been     carried out using HPPD inhibitor herbicides, exhibits a visually     determinable phytotoxicity with respect to those HPPD inhibitor     herbicides; -   b) in a second step, the phytotoxicity of soya varieties when grown     as a subsequent crop to maize wherein weed control has been carried     out using HPPD inhibitor herbicides is determined in relation to     that reference soya variety in the form of a factor; and -   c) in a third step, said soya varieties are labeled with said     factor.     Method Step a):

In the context of the present invention, the term “visually determinable phytotoxicity” is to be understood as being phytotoxic damage that is clearly visible. That value is preferably from 5 to 60% phytotoxicity, more especially from 5 to 20% phytotoxicity.

Suitable reference soya varieties within the scope of the present invention are those varieties which can be tested in agronomic, biological, biochemical, molecular-biological, physical or chemical test procedures in the field, in the greenhouse, in climatic cabins, in climatic cabinets, in the form of whole plants, cell cultures, organelle cultures, in soil, in nutrient solutions, in hydrocultures, in gelled nutrient media or in some other suitable form and exhibit measurable damage caused by residues of HPPD inhibitors in the soil. Particularly suitable are varieties that have comparable sensitivity or are more sensitive to those HPPD inhibitors than the variety NK S40-R9. Varieties that are only slightly (e.g. less than a factor of 2 with respect to the ED₂₀ of variety NK S40-R9; see Table C) more tolerant than variety NK S40-R9 in a measurable form are likewise designated sensitive.

Preferred sensitive reference soya varieties are varieties selected from NK S40-R9, Pioneer 94B01, NK S46-W8, Mustang M-222RR, AGI 7370 RR, Pioneer 9492, Pioneer 93B67, Pioneer 90B51, S. Grow SG948R and Pioneer 94B54.

Method Step b):

The factor in Method step b) can be expressed in letters, numbers, symbols, colours or other visual or acoustic signals or in words. For example, the factors can be indicated by the letters A, B, C, D and E. The reference soya variety is given a fixed reference value, for example “C”. The phytotoxicity of the soya varieties is indicated with reference to that factor. For example, a soya variety having two times higher resistance to the HPPD inhibitor herbicides can be given the factor “D”, while a soya variety having four times higher resistance to the HPPD inhibitor herbicides can be given the factor “E”. A soya variety having the factor “B” would be less suitable as a subsequent crop to maize when weed control in that maize crop had been carried out using HPPD inhibitor herbicides, while a soya variety having the factor “A” would be unsuitable. Alternatively, for example, numbers from 1 to 10 could be used, the fixed point of the reference soya variety being chosen as desired, or terms such as “low suitability”, “suitability”, “good suitability” and “very good suitability” or “non-tolerant” and “tolerant” could be used. It is also possible to give factors that relate to the application of specific HPPD inhibitor herbicides, for example the commercially available herbicides mesotrione, isoxaflutole or sulcotrione. Factors indicating the phytotoxicity of the soya crops with respect to specific HPPD inhibitor herbicides are more exact, which further increases the reliability of use.

Method Step c):

The labeling of a soya variety with a factor can be made accessible to the user in various ways. The factor can be indicated on or inside the product packaging or in an accompanying leaflet or it can be given in lists or tabular works in documents (publications, posters, leaflets) or on electronic or optical data supports or on the Internet, television or video, or made available as part of interactive programs or business methods for improving methods and yields in agriculture. The factor can also be publicised by direct oral communication (conversation, lecture, radio, telephone).

Biological Test Method for the Selection of Suitable Sensitive Reference Soybean Varieties in the Field:

-   -   a) Compound No. 2.13 according to Table 2 below was applied pre-         or post-emergence to maize in three repetitions in a field in         the vicinity of Ames, Iowa, USA, under practical conditions at a         suitable time (pre-emergence April-May; post-emergence May-June)         in a field trial using concentrations of 100, 200 and 400 g         a.i./ha. Application of fertilizer, pest control and other         cultivation measures were carried out in accordance with the         standards customary in agriculture. Because not all weeds were         controlled by the test herbicides, the test plots were kept         weed-free over the entire vegetation period by the application         of non-soil-active herbicides.     -   b) The plots were harvested and labeled in the autumn. At the         customary time in early summer (April/May) of the following         year, the soybeans to be tested were sown in the labeled plots         from the previous year and the condition of the plants on         reaching the different physiological growth stages was evaluated         (see Table 1).     -   c) The evaluation was carried out in % general phytotoxicity,         which records any effects such as growth inhibition, bleaching,         chlorosis, scorching or thinning. 0-4% phytotoxicity is         acceptable, >4% is not acceptable under practical field         conditions.

Tables A and B: Phytotoxicity of the soya varieties S40R-9 and S24-K4 as a subsequent crop to maize in which weed control has been carried out using the herbicide of formula 2.13. The herbicide was applied in an amount of 400 g/ha; in Table B an oil adjuvant (Agridex) was additionally used in an amount of 1.25% by volume.

TABLE A Days after Development stage of Soya Soya Days HPPD % Phytotoxicity the crop plant on evaluation sowing after Soya herbicide (mean evaluation date date sowing variety application value) (minimum/maximum) 18.06.03 20.05.03 29 NK S40-R9 404 6.67 BBCH12/BBCH13 18.06.03 20.05.03 29 NK-S24-K4 404 0 BBCH12/BBCH13 01.07.03 20.05.03 42 NK S40-R9 417 13 BBCH14/BBCH14 01.07.03 20.05.03 42 NK-S24-K4 417 0 BBCH14/BBCH14 15.07.03 20.05.03 56 NK S40-R9 431 14.33 BBCH16/BBCH17 15.07.03 20.05.03 56 NK-S24-K4 431 0 BBCH16/BBCH17

TABLE B Days after Development stage of Soya Soya Days HPPD % Phytotoxicity the crop plant on evaluation sowing after Soya herbicide (mean evaluation date date sowing variety application value) (minimum/maximum) 18.06.03 20.05.03 29 NK S40-R9 404 36.67 BBCH12/BBCH13 18.06.03 20.05.03 29 NK-S24-K4 404 5.67 BBCH12/BBCH13 01.07.03 20.05.03 42 NK S40-R9 417 49.33 BBCH14/BBCH14 01.07.03 20.05.03 42 NK-S24-K4 417 3.33 BBCH14/BBCH14 15.07.03 20.05.03 56 NK S40-R9 431 56.67 BBCH16/BBCH17 15.07.03 20.05.03 56 NK-S24-K4 431 1.67 BBCH16/BBCH17

It can be seen from the above results that the variety S40R-9 reacts very sensitively to the residues of the HPPD inhibitors and exhibits a “carry-over” effect, while the variety S24-K4 is largely resistant.

Test Method for the Selection of Suitable Soybean Varieties: Categorisation of the Soybean Varieties According to Their Sensitivity to HPPD Herbicide Residues and Comparison with Sensitive and Non-Sensitive Soybean Varieties:

-   -   1. A non-sterilised soil is treated with the HPPD inhibitor         being tested. The HPPD inhibitor being tested is applied in         concentrations of 0, 20, 40 and 80 ppb and incorporated         homogeneously into the soil. The soil so treated is then         introduced into pots (2⅝ inch×2⅝ inch×3½ inch) and lightly         firmed.     -   2. Sowing: The soybean varieties being tested are sown in the         pots treated as described above as follows: 3 seed grains are         used per pot, the seeds being pressed lightly into the soil         (under the surface of the soil) and covered over with soil. In         each test, varieties having known sensitivity are also tested as         reference. These are the soybean varieties NK S40-R9 and Pioneer         P94B01. Shortly after germination, the plants are thinned out to         two plants per pot. The plants receive an optimum supply of         water and nutrients and are kept in a greenhouse at 20-24° C.,         with 16 hours exposure to light per day.     -   3. 3-4 Weeks after sowing, the condition of the plants is         evaluated visually. Symptoms of damage to the plants, such as         chlorosis, bleaching and growth inhibition (‘stunting’), are         assessed and compared with an untreated soya plant of the same         variety.     -   4. Calculation: The repetitions are combined and a linear         regression analysis is carried out with non-transformed data.         ED₂₀ values (=effective dose at which damage is 20% in         comparison with the untreated control) are calculated from the         regression curve for each variety. The soybeans are grouped         according to whether they are “sensitive” or “tolerant” by         comparing the ED₂₀ values of the test varieties with those of         the standard varieties, that is to say by determining a factor         with respect to the reference variety.

Results relating to the selection and confirmation of suitable sensitive reference soybean varieties in the field. Ranking of soybean sensitivity and comparison with sensitive and non-sensitive soybean varieties.

The following Table C shows factors for the selection of suitable soybean varieties. As HPPD inhibitor herbicide there was used the herbicide of formula 2.13 of Table 2 indicated below.

TABLE C Factor with respect to reference variety NK S40-R9, based on ED20 values: Soya variety Factor NK S46-W8 0.5 Pioneer 94B01 0.8 Mustang M-222RR 0.8 AGI 7370 RR 1.0 Pioneer 9492 1.0 NK S40-R9 1.0 Pioneer 93B67 1.1 Pioneer 90B51 1.1 S. Grow SG948RR 1.2 Pioneer 94B54 1.6 Pioneer 91B91 3.0 Kruger 279 RR 3.4 NK S24-K4 3.6 Garst 2677 RR 4.1 Dekalb DKB36-51 4.2 Pioneer P92B38 4.3 Kruger 323 RR 4.3 MFA RT 3660N 4.3 D King 4868RR 4.4 Asgrow AG1401 RR 4.5 Beck's 336NRR 4.5 S34-A9 STS 8.0 Asgrow AG3902 4.7 Agripro 2547 RR/N 4.7 Asgrow AG2302 4.7 Pioneer 91B33 4.9 Beck's 366NRR 4.9 Asgrow 2705 5.0 S21-H7 STS 5.03 NK S35-A6 5.3 Dekalb DK32-51 5.3 Agripro 2502 RR 5.3 Asgrow 1602 5.4 Agway APK256 RR 5.6 Dekalb DKB23-51 5.8 Gld H H3505RR 5.8 Asgrow 2105 6.5 Asgrow AG4403 8.5 Agway APK 190 12.2

The following Table D shows factors for the selection of suitable soybean varieties. As HPPD inhibitor herbicide there was used the herbicide of formula 2.04 of Table 2 indicated below.

TABLE D Factor with respect to reference variety NK S40-R9, based on ED20 values: Soya variety Factor S40-R9 1.0 S21-H7 STS 3.45 S34-A9 STS 4.56

The following Table E shows factors for the selection of suitable soybean varieties. As HPPD inhibitor herbicide there was used the herbicide of formula 2.10 of Table 2 indicated below.

TABLE E Factor with respect to reference variety NK S40-R9, based on ED20 values: Soya variety Factor S40-R9 1.0 S21-H7 STS 3.00 S34-A9 STS 3.40

The reference variety S40-R9 is assigned factor 1. Soya varieties having a factor greater than 3, preferably greater than 3.5, are suitable as a subsequent crop to maize when weed control in that maize crop has been carried out using HPPD inhibitor herbicides. Soya varieties having a factor between 3 and 2 are less suitable, while soya varieties having a factor of less than 2 are unsuitable. The higher the factor, the better the suitability of the soya variety.

The method according to the invention is not limited in respect of the HPPD inhibitor herbicides used. Examples of compounds of the class of HPPD inhibitors are compounds of formula I

wherein Q is an organic substituent which is so chosen that the compound of formula I has a pK value of from 1 to 5;

-   T is T₁

wherein

-   D is hydrogen or R₃; -   E is hydrogen or R₄; or -   D and E together are C₂-C₃alkylene which can be mono- or     poly-substituted by R₆; -   A is C₁-C₂alkylene which can be mono- or poly-substituted by R₅; or     A may additionally be carbonyl, oxygen or —N—R₇— when D and E are     other than C₂-C₃alkylene; -   R₁, R₂, R₃, R₄, R₅ and R₆ are each independently of the others     hydrogen, C₁-C₄alkyl, phenyl, C₁-C₄alkoxy, halogen, hydroxy, cyano,     hydroxycarbonyl or C₁-C₄alkoxycarbonyl; -   or R₂ and R₄ together form a C₂-C₄alkylene chain which can be     interrupted by oxygen and/or carbonyl and/or sulfur, with the     proviso that the oxygen and sulfur atoms are separated by at least     one methylene group; -   R₇ is C₁-C₄alkyl, alkoxycarbonyl or C₁-C₄alkylcarbonyl; -   R₀₃₆ is hydroxy, O⁻M⁺, wherein M⁺ is an alkali metal cation or     ammonium cation, halogen, C₁-C₁₂alkylsufonyloxy, amino,     C₁-C₄alkylthio, C₁-C₁₂alkylsulfinyl, C₁-C₁₂alkylsulfonyl,     C₁-C₁₂haloalkylthio, C₁-C₁₂haloalkylsulfinyl,     C₁-C₁₂haloalkylsulfonyl, C₁-C₆alkoxy-C₁-C₆alkylthio,     C₁-C₆alkoxy-C₁-C₆alkylsulfinyl, C₁-C₆alkoxy-C₁-C₆alkylsulfonyl,     C₃-C₁₂alkenylthio, C₃-C₁₂alkenylsulfinyl, C₃-C₁₂alkenylsulfonyl,     C₃-C₁₂alkynylthio, C₃-C₁₂alkynylsulfinyl, C₃-C₁₂alkynylsulfonyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfinyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfonyl, (C₁-C₄alkoxy)₂P(O)O,     C₁-C₄alkyl-(C₁-C₄alkoxy)P(O)O, H(C₁-C₄alkoxy)P(O)O, R₀₃₇R₀₃₈N,     R₀₃₉R₀₄₀NNH, R₀₄₁R₀₄₂NNC(O)O—, R₀₄₃R₀₄₄NC(O)NH—,     C₁-C₁₈alkylcarbonyloxy, C₂-C₁₈alkenylcarbonyloxy,     C₂-C₁₈alkynylcarbonyloxy, C₃-C₆cycloalkylcarbonyloxy,     C₁-C₁₂alkoxycarbonyloxy, C₁-C₁₂alkylthiocarbonyloxy or     C₁-C₁₂alkylthiocarbamoyl, wherein the alkyl, alkenyl and alkynyl     groups can be substituted by halogen, C₁-C₆alkoxy, C₁-C₆alkylthio,     C₁-C₆alkylsulfinyl, C₁-C₆alkylsulfonyl or by cyano; or -   R₀₃₆ is phenoxy, phenylthio, phenylsulfinyl, phenylsulfonyl,     phenylsulfonylamino, phenylsulfonyloxy, benzoyloxy or     benzoyl-C₁-C₆alkoxy, wherein the phenyl groups may in turn be     substituted one or more times by halogen, nitro, cyano, C₁-C₄alkyl,     C₁-C₄haloalkyl, C₁-C₄alkoxy and/or C₁-C₄haloalkoxy, -   or R₀₃₆ is a group Het₀₇-thio, Het₀₈-sulfinyl, Het₀₉-sulfonyl,     Het₀₁₀-(CO)O or Het₀₁₁-N(R₀₄₇);     wherein -   Het₀₇, Het₀₈, Het₀₉, Het₀₁₀ and Het₀₁₁ are each independently of the     others a five- to ten-membered monocyclic or annellated bicyclic     ring system which may be aromatic or partially saturated and may     contain from 1 to 4 hetero atoms selected from nitrogen, oxygen and     sulfur, and each ring system may contain not more than two oxygen     atoms and not more than two sulfur atoms, and the ring system itself     can be substituted by C₁-C₆alkyl, C₁-C₆haloalkyl, C₁-C₆alkoxy,     C₁-C₆haloalkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, di(C₁-C₄alkyl)aminosulfonyl,     di(C₁-C₄alkyl)amino, halogen, cyano, nitro or by phenyl, and the     substituents on the nitrogen atom in the heterocyclic ring are other     than halogen; -   R₀₃₇, R₀₃₈, R₀₃₉, R₀₄₀, R₀₄₁, R₀₄₂, R₀₄₃, R₀₄₄ and R₀₄₇ are each     independently of the others hydrogen or C₁-C₆alkyl; or -   R₀₃₇ and R₀₃₈ together or R₀₃₉ and R₀₄₀ together or R₀₄₁ and R₀₄₂     together or R₀₄₃ and R₀₄₄ together are pyrrolidino, piperidino,     morpholino or thiomorpholino, which can be mono- or poly-substituted     by methyl groups; -   or T is T₂

wherein

-   R₃₄ is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl,     C₂-C₄alkenyl, C₂-C₄alkynyl or benzyl, it being possible for the     phenyl group to be substituted one or more times by C₁-C₆alkyl,     C₁-C₆haloalkyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen, cyano,     hydroxy and/or nitro; -   R₃₅ is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl,     C₃-C₄alkenyl, C₃-C₄alkynyl or benzyl, it being possible for the     phenyl group to be substituted one or more times by C₁-C₆alkyl,     C₁-C₆haloalkyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen, cyano,     hydroxy and/or nitro; -   R₃₆ is hydroxy, O⁻M⁺, wherein M⁺ is an alkali metal cation or     ammonium cation, halogen, C₁-C₁₂alkylsulfonyloxy, amino,     C₁-C₄alkylthio, C₁-C₁₂alkylsulfinyl, C₁-C₁₂alkylsulfonyl,     C₁-C₁₂haloalkylthio, C₁-C₁₂haloalkylsulfinyl,     C₁-C₁₂haloalkylsulfonyl, C₁-C₆alkoxy-C₁-C₆alkylthio,     C₁-C₆alkoxy-C₁-C₆alkylsulfinyl, C₁-C₆alkoxy-C₁-C₆alkylsulfonyl,     C₃-C₁₂alkenylthio, C₃-C₁₂alkenylsulfinyl, C₃-C₁₂alkenylsulfonyl,     C₃-C₁₂alkynylthio, C₃-C₁₂alkynylsulfinyl, C₃-C₁₂alkynylsulfonyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfinyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfonyl, (C₁-C₄alkoxy)₂P(O)O,     C₁-C₄alkyl-(C₁-C₄alkoxy)P(O)O, H(C₁-C₄alkoxy)P(O)O, R₃₇R₃₈N,     R₃₉R₄₀NNH, R₄₁R₄₂NC(O)O—, R₄₃R₄₄NC(O)NH—, C₁-C₁₈alkylcarbonyloxy,     C₂-C₁₈alkenylcarbonyloxy, C₂-C₁₈alkynylcarbonyloxy,     C₃-C₆cycloalkylcarbonyloxy, C₁-C₁₂alkoxycarbonyloxy,     C₁-C₁₂alkylthiocarbonyloxy or C₁-C₁₂alkylthiocarbamoyl, wherein the     alkyl, alkenyl and alkynyl groups can be substituted by halogen,     C₁-C₆alkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl, C₁-C₆alkylsulfonyl     or by cyano; or -   R₃₆ is phenoxy, phenylthio, phenylsulfinyl, phenylsulfonyl,     phenylsulfonylamino, phenylsulfonyloxy, benzoyloxy or     benzoyl-C₁-C₆alkoxy, it being possible for the phenyl groups in turn     to be substituted one or more times by halogen, nitro, cyano,     C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy and/or C₁-C₄haloalkoxy, -   or R₃₆ is a group Het₇-thio, Het₈-sulfinyl, Het₉-sulfonyl,     Het₁₀-(CO)O or Het₁₁-N(R₄₇); wherein Het₇, Het₈, Het₉, Het₁₀ and     Het₁₁ are each independently of the others a five- to ten-membered     monocyclic or annellated bicyclic ring system which may be aromatic     or partially saturated and may contain from 1 to 4 hetero atoms     selected from nitrogen, oxygen and sulfur, and each ring system may     contain not more than two oxygen atoms and not more than two sulfur     atoms, and the ring system itself can be substituted by C₁-C₆alkyl,     C₁-C₆haloalkyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, C₁-C₆alkylthio,     C₁-C₆alkylsulfinyl, C₁-C₆alkylsulfonyl, di(C₁-C₄alkyl)aminosulfonyl,     di(C₁-C₄alkyl)amino, halogen, cyano, nitro or by phenyl, and the     substituents on the nitrogen atom in the heterocyclic ring are other     than halogen; -   R₃₇, R₃₈, R₃₉, R₄₀, R₄₁, R₄₂, R₄₃, R₄₄ and R₄₇ are each     independently of the others hydrogen or C₁-C₆alkyl; or -   R₃₇ and R₃₈ together or R₃₉ and R₄₀ together or R₄₁ and R₄₂ together     or R₄₃ and R₄₄ together are pyrrolidino, piperidino, morpholino or     thiomorpholino, which can be mono- or poly-substituted by methyl     groups; -   or T is T₃

wherein

-   R₄₉ is C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl or     halo-substituted C₃-C₆cycloalkyl; -   Z₀₁ is a chemical bond, S, SO or SO₂; -   R₅₀ is hydrogen or C₁-C₃alkylene which can be substituted by the     following substituents: halogen, hydroxy, C₁-C₆alkoxy, C₂-C₆alkenyl,     C₂-C₆alkynyl, C₃-C₆cycloalkyl, C₁-C₆alkoxy-C₁-C₆alkoxy,     C₁-C₆alkoxy-C₁-C₆alkoxy-C₁-C₆alkoxy, (3-oxetanyl)-oxy,     C₁-C₆alkyl-substituted (3-oxetanyl)-oxy, benzylthio, benzylsulfinyl,     benzylsulfonyl, phenyl, phenoxy, phenylthio, phenylsulfinyl or     phenylsulfonyl, it being possible for the phenyl- and     benzyl-containing groups in turn to be substituted by one or more     C₁-C₆alkyl, C₁-C₆haloalkyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen,     cyano, hydroxy and/or nitro groups; -   or R₅₀ is phenyl, it being possible for the phenyl-containing group     in turn to be substituted by one or more C₁-C₆alkyl, C₁-C₆haloalkyl,     C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen, cyano, hydroxy and/or nitro     groups, -   or R₅₀ is C₃-C₆cycloalkyl, C₁-C₆alkoxy- or C₁-C₆alkyl-substituted     C₃-C₆cycloalkyl, 3-oxetanyl or C₁-C₆alkyl-substituted 3-oxetanyl; -   or T is T₄

wherein

-   R₀₄₅ is C₁-C₆alkyl, C₁-C₆haloalkyl, C₃-C₆cycloalkyl or     halo-substituted C₃-C₆cycloalkyl; -   and their agronomically acceptable salts, isomers and enantiomers.

The compounds of formula I also include the salts which the compounds are able to form with amines, alkali metal and alkaline earth metal bases or quaternary ammonium bases. Among the alkali metal and alkaline earth metal hydroxides as salt formers, special mention should be made of the hydroxides of lithium, sodium, potassium, magnesium and calcium, but especially the hydroxides of sodium and potassium.

Examples of amines suitable for ammonium salt formation include ammonia as well as primary, secondary and tertiary C₁-C₁₈alkylamines, C₁-C₄hydroxyalkylamines and C₂-C₄alkoxyalkylamines, for example methylamine, ethylamine, n-propylamine, isopropylamine, the four butylamine isomers, n-amylamine, isoamylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, methylethylamine, methylisopropylamine, methylhexylamine, methylnonylamine, methylpentadecylamine, methyloctadecylamine, ethylbutylamine, ethylheptylamine, ethyloctylamine, hexylheptylamine, hexyloctylamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, di-n-amylamine, diisoamylamine, dihexylamine, diheptylamine, dioctylamine, ethanolamine, n-propanolamine, isopropanolamine, N,N-diethanolamine, N-ethylpropanolamine, N-butylethanolamine, allylamine, n-but-2-enylamine, n-pent-2-enylamine, 2,3-dimethylbut-2-enylamine, dibut-2-enylamine, n-hex-2-enylamine, propylenediamine, trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, triisobutylamine, tri-sec-butylamine, tri-n-amylamine, methoxyethylamine and ethoxyethylamine; heterocyclic amines, for example pyridine, quinoline, isoquinoline, morpholine, piperidine, pyrrolidine, indoline, quinuclidine and azepine; primary arylamines, for example anilines, methoxyanilines, ethoxyanilines, o-, m- and p-toluidines, phenylenediamines, benzidines, naphthylamines and o-, m- and p-chloroanilines; but especially triethylamine, isopropylamine and diisopropylamine.

Because the compounds of formula I wherein T is T₁ are preferably in enolised forms or in the form of salts, formula I also includes the enolised forms of formulae Ia, Ib, Ic and Id wherein M is hydrogen or a metal ion or an ammonium ion.

Since compounds of formula I may also contain asymmetric carbon atoms, for example in the case of the carbon atom carrying R₁, D and A, all stereoisomeric forms are also included.

Q is especially an organic substituent which is so chosen that the compound of formula I has a pK value of from 2.5 to 4.

The organic substituent Q may be an inert substituent of any desired structure, provided that the compounds of formula I retain their action as HPPD inhibitors.

Q is preferably a mono- or poly-substituted phenyl, pyridyl or heteroaryl group, especially 2-benzoyl, 2-isonicotinoyl and 2-nicotinoyl derivatives, the substitution pattern of those groups being freely selectable provided that the compounds of formula I retain their action as HPPD inhibitors.

HPPD inhibitors especially suitable for the method according to the invention are compounds of formula I wherein

-   Q is Q₁

wherein

-   A₁ is methine, CRa₁ or ═N—(O)_(p); -   p is 0 or 1; -   Ra₁ is C₁-C₆alkyl, hydroxy, C₁-C₆alkoxy, C₁-C₆haloalkoxy,     C₃-C₆alkenyloxy, C₃-C₆haloalkenyloxy, C₃-C₆alkynyloxy,     C₁-C₄alkylcarbonyloxy, C₁-C₄alkylsulfonyloxy, tosyloxy,     C₁-C₄alkylthio, C₁-C₄alkylsulfinyl, C₁-C₄alkylsulfonyl,     C₁-C₄alkylamino, C₁-C₄dialkylamino, C₁-C₄alkoxycarbonyl,     C₁-C₄haloalkyl, formyl, cyano, halogen, phenyl or phenoxy; it being     possible for phenyl in turn to be substituted by C₁-C₃alkyl,     C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano and/or     by nitro; -   or Ra₁ is a three- to ten-membered monocyclic ring system or,     together with Ra₂ or Ra₅, an annellated mono- or bi-cyclic ring     system which may be interrupted by oxygen, sulfur, SO, SO₂, NRa₆,     carbonyl and/or by ═NORa₇, the ring system, unless it is annellated,     being bonded to the carbon atom of the substituent A directly or by     way of a C₁-C₄alkylene, —CH═CH—, —C≡C—, —CH₂O—, —CH₂N(C₁-C₄alkyl)-,     —CH₂S—, —CH₂SO—, or —CH₂SO₂— group, and the ring system may contain     not more than two oxygen atoms and not more than two sulfur atoms,     and the ring system can itself be mono-, di- or tri-substituted by     C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl, C₂-C₆haloalkenyl,     C₂-C₆alkynyl, C₂-C₆haloalkynyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy,     C₃-C₆alkenyloxy, C₃-C₆alkynyloxy, C₁-C₆alkylthio,     C₁-C₆haloalkylthio, C₃-C₆alkenylthio, C₃-C₆haloalkenylthio,     C₃-C₆alkynylthio, C₁-C₄alkoxy-C₁-C₂alkylthio,     C₁-C₄alkylcarbonyl-C₁-C₂alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₂alkylthio, cyano-C₁-C₄alkylthio,     C₁-C₆alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆alkylsulfonyl,     C₁-C₆haloalkylsulfonyl, aminosulfonyl, C₁-C₂alkylaminosulfonyl,     di(C₁-C₂alkyl)aminosulfonyl, di(C₁-C₄alkyl)amino, halogen, cyano,     nitro, phenyl and/or benzylthio, it being possible for phenyl and     benzylthio in turn to be substituted on the phenyl ring by     C₁-C₃alkyl, C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen,     cyano or by nitro, and substituents on the nitrogen atom in the     heterocyclic ring are other than halogen; -   or Ra₁ is the group —X₅-X₇ or the group —X₆-X₅-X₇; wherein -   X₆ is a C₁-C₆alkylene, C₃-C₆alkenylene or C₃-C₆alkynylene chain     which can be mono- or poly-substituted by halogen and/or by X₈, the     unsaturated bonds of the chain not being bonded directly to the     substituent X₅; -   X₈ is hydroxy, C₁-C₆alkoxy, C₃-C₆cycloalkyloxy,     C₁-C₆alkoxy-C₁-C₆alkoxy, C₁-C₆alkoxy-C₁-C₆alkoxy-C₁-C₆alkoxy or     C₁-C₂alkylsulfonyloxy; -   X₅ is oxygen, —O(CO)—, —(CO)O—, —O(CO)O—, —N(C₁-C₄alkyl)-O—,     —O—N(C₁-C₄alkyl)-, thio, sulfinyl, sulfonyl, —SO₂N(C₁-C₄alkyl)-,     —N(C₁-C₄alkoxy)SO₂—, —N(C₁-C₄alkyl)SO₂—,     —N(C₁-C₂alkoxy-C₁-C₂alkyl)SO₂— or —N(C₁-C₄alkyl)-; -   Ra₆ is hydrogen, C₁-C₄alkyl, C₁-C₄alkythio-C₁-C₄carbonyl,     C₁-C₄alkylsulfinyl-C₁-C₄carbonyl, C₁-C₄alkylsulfonyl-C₁-C₄carbonyl,     C₁-C₄alkoxycarbonyl, C₁-C₄alkylcarbonyl, phenylcarbonyl or phenyl,     it being possible for the phenyl groups in turn to be substituted by     C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy, C₁-C₄haloalkoxy,     C₁-C₄alkylcarbonyl, C₁-C₄alkoxycarbonyl, C₁-C₄alkylamino,     di-C₁-C₄alkylamino, C₁-C₄alkyl-S—, C₁-C₄alkyl-SO—, C₁-C₄alkyl-SO₂,     C₁-C₄alkyl-S(O)₂O, C₁-C₄haloalkyl-S—, C₁-C₄haloalkyl-SO,     C₁-C₄haloalkyl-SO₂, C₁-C₄haloalkyl-S(O)₂O, C₁-C₄alkyl-S(O)₂NH,     C₁-C₄alkyl-S(O)₂N(C₁-C₄alkyl), halogen, nitro or by cyano; -   Ra₇ is C₁-C₄alkyl; -   Ra₂ is hydrogen, C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl,     C₂-C₆haloalkenyl, vinyl substituted by C₁-C₂alkoxycarbonyl or by     phenyl, C₂-C₆alkynyl, C₂-C₆haloalkynyl, ethynyl substituted by     trimethylsilyl, hydroxy, C₁-C₂alkoxy, C₁-C₂alkoxycarbonyl or by     phenyl, C₃-C₆allenyl, C₃-C₆cycloalkyl, halo-substituted     C₃-C₆cycloalkyl, C₁-C₆alkoxy, C₃-C₆alkenyloxy, C₃-C₆alkynyloxy,     C₁-C₆haloalkoxy, C₃-C₆haloalkenyloxy, cyano-C₁-C₄alkoxy,     C₁-C₄alkoxy-C₁-C₄alkoxy, C₁-C₄alkylthio-C₁-C₄alkoxy,     C₁-C₄alkylsulfinyl-C₁-C₄alkoxy, C₁-C₄alkylsulfonyl-C₁-C₄alkoxy,     C₁-C₄alkoxycarbonyl-C₁-C₄alkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylthio, C₁-C₆haloalkylsulfinyl,     C₁-C₆haloalkylsulfonyl, C₁-C₄alkoxycarbonyl-C₁-C₄alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfinyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfonyl, benzyl-S—, benzyl-SO—,     benzyl-SO₂—, C₁-C₆alkylamino, C₂-C₆dialkylamino,     C₁-C₆alkylaminosulfonyl, di(C₁-C₆alkylamino)sulfonyl, benzyloxy,     benzyl, phenyl, phenoxy, phenylthio, phenylsulfinyl or     phenylsulfonyl, it being possible for the phenyl-containing groups     in turn to be substituted by C₁-C₃alkyl, C₁-C₃haloalkyl,     C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by nitro, or Ra₂ is     OS—C₁-C₄alkyl, OSO—C₁-C₄alkyl, OSO₂—C₁-C₄alkyl, OS—C₁-C₄haloalkyl,     OSO—C₁-C₄-haloalkyl, OSO₂—C₁-C₄haloalkyl,     N(C₁-C₄alkyl)-S—C₁-C₄alkyl, N(C₁-C₄alkyl)-SO—C₁-C₄alkyl,     N(C₁-C₄alkyl)-SO₂—C₁-C₄alkyl, cyano, carbamoyl, C₁-C₄alkoxycarbonyl,     formyl, halogen, rhodano, amino, hydroxy-C₁-C₄alkyl,     C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkyl-S—C₁-C₄alkyl,     C₁-C₄alkyl-SO—C₁-C₄alkyl, C₁-C₄alkyl-SO₂—C₁-C₄alkyl,     cyano-C₁-C₄alkyl, C₁-C₆alkylcarbonyloxy-C₁-C₄alkyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄alkoxycarbonyloxy-C₁-C₄alkyl,     C₁-C₄rhodano-C₁-C₄alkyl, benzoyloxy-C₁-C₄alkyl, C₂-C₆oxiranyl,     C₁-C₄alkylamino-C₁-C₄alkyl, di(C₁-C₄alkyl)amino-C₁-C₄alkyl,     C₁-C₁₂alkylthiocarbonyl-C₁-C₄alkyl or formyl-C₁-C₄alkyl, or Ra₂ is a     five- to ten-membered monocyclic or annellated bicyclic ring system     which may be aromatic or partially saturated and may contain from 1     to 4 hetero atoms selected from nitrogen, oxygen and sulfur, the     ring system being bonded to the pyridine ring by way of a     C₁-C₄alkylene, —CH═CH—, —C≡C—, —CH₂O—, —CH₂N(C₁-C₄alkyl)-, —CH₂SO—     or —CH₂SO₂— group, and each ring system may contain not more than     two oxygen atoms and not more than two sulfur atoms, and the ring     system itself can be mono-, di- or tri-substituted by C₁-C₆alkyl,     C₁-C₆haloalkyl, C₃-C₆alkenyl, C₃-C₆haloalkenyl, C₃-C₆alkynyl,     C₃-C₆haloalkynyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, C₃-C₆alkenyloxy,     C₃-C₆alkynyloxy, mercapto, C₁-C₆alkylthio, C₁-C₆haloalkylthio,     C₃-C₆alkenylthio, C₃-C₆haloalkenylthio, C₃-C₆alkynylthio,     C₂-C₅alkoxyalkylthio, C₃-C₅acetylalkylthio,     C₃-C₆alkoxycarbonylalkylthio, C₂-C₄cyanoalkylthio,     C₁-C₆alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆alkylsulfonyl,     C₁-C₆haloalkylsulfonyl, aminosulfonyl, C₁-C₂alkylaminosulfonyl,     di(C₁-C₂alkyl)aminosulfonyl, di(C₁-C₄alkyl)amino, halogen, cyano,     nitro, phenyl and/or by benzylthio, it being possible for phenyl and     benzylthio in turn to be substituted on the phenyl ring by     C₁-C₃alkyl, C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen,     cyano or by nitro, and substituents on the nitrogen atom in the     heterocyclic ring are other than halogen; -   or Ra₂ is the group —X₁-X₃ or the group —X₂-X₁-X₃; wherein -   X₂ is a C₁-C₆alkylene, C₃-C₆alkenylene or C₃-C₆alkynylene chain     which can be mono- or poly-substituted by halogen or by X₄, the     unsaturated bonds of the chain not being bonded directly to the     substituent X₁; -   X₄ is hydroxy, C₁-C₆alkoxy, C₃-C₆cycloalkyloxy,     C₁-C₆alkoxy-C₁-C₆alkoxy, C₁-C₆alkoxy-C₁-C₆alkoxy-C₁-C₆alkoxy or     C₁-C₂alkylsulfonyloxy; -   X₁ is oxygen, —O(CO)—, —(CO)O—, —O(CO)O—, —N(C₁-C₄alkyl)-O—,     —O—N(C₁-C₄alkyl)-, thio, sulfinyl, sulfonyl, —SO₂N(C₁-C₄alkyl)-,     —N(C₁-C₄alkyl)SO₂—, —N(C₁-C₂alkoxy-C₁-C₂alkyl)SO₂— or     —N(C₁-C₄alkyl)-; -   X₃ and X₇ are each independently of the other a C₁-C₈alkyl,     C₃-C₆alkenyl or C₃-C₆alkynyl group which is mono- or     poly-substituted by the following substituents: halogen, hydroxy,     amino, formyl, nitro, cyano, mercapto, carbamoyl, C₁-C₆alkoxy,     C₁-C₆alkoxycarbonyl, C₂-C₆alkenyl, C₂-C₆haloalkenyl, C₂-C₆alkynyl,     C₂-C₆haloalkynyl, C₃-C₆cycloalkyl, halo-substituted C₃-C₆cycloalkyl,     C₃-C₆alkenyloxy, C₃-C₆alkynyloxy, C₁-C₆haloalkoxy,     C₃-C₆haloalkenyloxy, cyano-C₁-C₆alkoxy, C₁-C₆alkoxy-C₁-C₆alkoxy,     C₁-C₆alkoxy-C₁-C₆alkoxy-C₁-C₆alkoxy, C₁-C₆alkylthio-C₁-C₆alkoxy,     C₁-C₆alkylsulfinyl-C₁-C₆alkoxy, C₁-C₆alkylsulfonyl-C₁-C₆alkoxy,     C₁-C₆alkoxycarbonyl-C₁-C₆alkoxy, C₁-C₆alkoxycarbonyl,     C₁-C₆alkylcarbonyl, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylthio, C₁-C₆haloalkylsulfinyl,     C₁-C₆haloalkylsulfonyl, oxiranyl, which can in turn be substituted     by C₁-C₆alkyl, (3-oxetanyl)-oxy, which can in turn be substituted by     C₁-C₆alkyl, benzylthio, benzylsulfinyl, benzylsulfonyl,     C₁-C₆alkylamino, di(C₁-C₆alkyl)amino, C₁-C₄alkyl-S(O)₂O,     C₁-C₄alkyl-N(C₁-C₄alkyl)SO₂—, rhodano, phenyl, phenoxy, phenylthio,     phenylsulfinyl and/or phenylsulfonyl; -   it being possible for the phenyl- or benzyl-containing groups in     turn to be substituted by one or more C₁-C₆alkyl, C₁-C₆haloalkyl,     C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen, cyano, hydroxy and/or nitro     groups, or -   X₃ and X₇ are each independently of the other phenyl which can be     substituted one or more times by C₁-C₆alkyl, C₁-C₆haloalkyl,     C₁-C₆alkoxy, C₁-C₆haloalkoxy, halogen, cyano, hydroxy and/or nitro;     or -   X₃ and X₇ are each independently of the other C₃-C₆cycloalkyl,     C₁-C₆alkoxy- or C₁-C₆alkylsubstituted C₃-C₆cycloalkyl, 3-oxetanyl or     C₁-C₆alkyl-substituted 3-oxetanyl; -   or X₃ and X₇ are each independently of the other a five- to     ten-membered monocyclic or annellated bicyclic ring system which may     be aromatic or saturated or partially saturated and may contain from     1 to 4 hetero atoms selected from nitrogen, oxygen and sulfur, the     ring system being bonded to the substituent X₁ or X₅ directly or by     way of a C₁-C₄alkylene, C₂-C₄alkenyl-C₁-C₄alkylene,     C₂-C₄alkynyl-C₁-C₄alkylene, —N(C₁-C₄alkyl)-C₁-C₄alkylene,     —SO—C₁-C₄alkylene or —SO₂—C₁-C₄alkylene group, and each ring system     may contain not more than two oxygen atoms and not more than two     sulfur atoms, and the ring system can itself be mono-, di- or     tri-substituted by C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl,     C₂-C₆haloalkenyl, C₂-C₆alkynyl, C₂-C₆haloalkynyl, C₁-C₆alkoxy,     hydroxy, C₁-C₆haloalkoxy, C₃-C₆alkenyloxy, C₃-C₆alkynyloxy,     mercapto, C₁-C₆alkylthio, C₁-C₆haloalkylthio, C₃-C₆alkenylthio,     C₃-C₆haloalkenylthio, C₃-C₆alkynylthio, C₂-C₅alkoxyalkylthio,     C₃-C₅acetylalkylthio, C₃-C₆alkoxycarbonylalkylthio,     C₂-C₄cyanoalkylthio, C₁-C₆alkylsulfinyl, C₁-C₆haloalkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylsulfonyl, aminosulfonyl,     C₁-C₂alkylaminosulfonyl, di(C₁-C₂alkyl)aminosulfonyl,     di(C₁-C₄alkyl)amino, halogen, cyano, nitro, phenyl and/or by     benzylthio, it being possible for phenyl and benzylthio in turn to     be substituted on the phenyl ring by C₁-C₃alkyl, C₁-C₃haloalkyl,     C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by nitro, and the     substituents on the nitrogen atom in the heterocyclic ring are other     than halogen; -   Ra₃ is hydrogen, C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl,     C₂-C₆haloalkenyl, C₂-C₆alkynyl, C₂-C₆haloalkynyl, C₃-C₆cycloalkyl,     C₁-C₆alkoxy, C₁-C₆haloalkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylthio, C₁-C₆haloalkylsulfinyl,     C₁-C₆haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆dialkylamino,     C₁-C₆alkylaminosulfonyl, C₂-C₆dialkylaminosulfonyl, phenyl,     phenylthio, phenylsulfinyl, phenylsulfonyl or phenoxy, it being     possible for phenyl in turn to be substituted by C₁-C₃alkyl,     C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by     nitro, or Ra₃ is —N(C₁-C₄alkyl)-S—C₁-C₄alkyl,     —N(C₁-C₄alkyl)-SO—C₁-C₄alkyl, —N(C₁-C₄alkyl)-SO₂—C₁-C₄alkyl, cyano,     halogen, amino, C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkyl-S—C₁-C₄alkyl,     C₁-C₄alkyl-SO—C₁-C₄alkyl or C₁-C₄alkyl-SO₂—C₁-C₄alkyl; -   Ra₄ is hydrogen, C₁-C₆alkyl, hydroxy, C₁-C₆alkoxy, C₁-C₆haloalkoxy,     C₃-C₆alkenyloxy, C₃-C₆haloalkenyloxy, C₃-C₆alkynyloxy,     C₁-C₄alkylcarbonyloxy, C₁-C₄alkylsulfonyloxy, tosyloxy,     C₁-C₄alkylthio, C₁-C₄alkylsulfinyl, C₁-C₄alkylsulfonyl,     C₁-C₄alkylamino, C₁-C₄-dialkylamino, C₁-C₄alkoxycarbonyl,     C₁-C₄haloalkyl, formyl, cyano, halogen, phenyl or phenoxy, it being     possible for phenyl in turn to be substituted by C₁-C₃alkyl,     C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by     nitro; -   or Ra₄ is a five- to ten-membered monocyclic ring system or, with     Ra₃, an annellated bicyclic ring system which may contain from 1 to     4 hetero atoms selected from nitrogen, oxygen and sulfur, the ring     system, unless it is annellated, being bonded to the ring containing     the substituent A directly or by way of a C₁-C₄alkylene, —CH═CH—,     —C≡C—, —CH₂O—, —CH₂N(C₁-C₄alkyl)-, —CH₂S—, —CH₂SO— or —CH₂SO₂—     group, and the ring system may contain not more than two oxygen     atoms and not more than two sulfur atoms, and the ring system can     itself be mono-, di- or tri-substituted by C₁-C₆alkyl,     C₁-C₆haloalkyl, C₂-C₆alkenyl, C₂-C₆haloalkenyl, C₂-C₆alkynyl,     C₂-C₆haloalkynyl, C₁-C₆alkoxy, C₁-C₆haloalkoxy, C₃-C₆alkenyloxy,     C₃-C₆alkynyloxy, C₁-C₆alkylthio, C₁-C₆haloalkylthio,     C₃-C₆alkenylthio, C₃-C₆haloalkenylthio, C₃-C₆alkynylthio,     C₁-C₄alkoxy-C₁-C₂alkylthio, C₁-C₄alkylcarbonyl-C₁-C₂alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₂alkylthio, cyano-C₁-C₄alkylthio,     C₁-C₆alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆alkylsulfonyl,     C₁-C₆haloalkylsulfonyl, aminosulfonyl, C₁-C₂alkylaminosulfonyl,     di(C₁-C₂alkyl)aminosulfonyl, di(C₁-C₄alkyl)amino, halogen, cyano,     nitro, phenyl and/or by benzylthio, it being possible for phenyl and     benzylthio in turn to be substituted on the phenyl ring by     C₁-C₃alkyl, C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen,     cyano or by nitro, and substituents on the nitrogen atom in the     heterocyclic ring are other than halogen; -   Ra₅ is hydrogen, C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl,     C₂-C₆haloalkenyl, C₂-C₆alkynyl, C₂-C₆haloalkynyl, C₃-C₆cycloalkyl,     C₁-C₆alkoxy, C₁-C₆haloalkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylthio, C₁-C₆haloalkylsulfinyl,     C₁-C₆haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆dialkylamino,     C₁-C₆alkylaminosulfonyl, C₂-C₆dialkylaminosulfonyl, phenyl,     phenylthio, phenylsulfinyl, phenylsulfonyl or phenoxy, it being     possible for phenyl in turn to be substituted by C₁-C₃alkyl,     C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by     nitro, or Ra₅ is —N(C₁-C₄alkyl)-S—C₁-C₄alkyl,     —N(C₁-C₄alkyl)-SO—C₁-C₄alkyl, —N(C₁-C₄alkyl)-SO₂—C₁-C₄alkyl, cyano,     halogen, amino, C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkyl-S—C₁-C₄alkyl,     C₁-C₄alkyl-SO—C₁-C₄alkyl or C₁-C₄alkyl-SO₂—C₁-C₄alkyl, and     agronomically acceptable salts/N-oxides/isomers/enantiomers of those     compounds.

In preferred compounds of formula I, T is T₁. Those compounds correspond to formula Iz

wherein the substituents are as defined for formula I.

The alkyl groups appearing in the above substituent definitions may be straight-chain or branched and are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl. Alkoxy, alkenyl and alkynyl radicals are derived from the mentioned alkyl radicals. The alkenyl and alkynyl groups may be mono- or poly-unsaturated. Alkoxy is, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or tert-butoxy. Alkoxycarbonyl is, for example, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, n-butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl or tert-butoxycarbonyl; preferably methoxycarbonyl or ethoxycarbonyl.

Halogen is generally fluorine, chlorine, bromine or iodine. The same is also true of halogen in conjunction with other meanings, such as haloalkyl or halophenyl.

Haloalkyl groups having a chain length of from 1 to 6 carbon atoms are, for example, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, 2,2,2-trifluoroethyl, 1-fluoroethyl, 2-fluoroethyl, 2-chloroethyl, 2-fluoroprop-2-yl, pentafluoroethyl, 1,1-difluoro-2,2,2-trichloroethyl, 2,2,3,3-tetrafluoroethyl and 2,2,2-trichloroethyl, pentafluoroethyl, heptafluoro-n-propyl and perfluoro-n-hexyl.

Alkenyl and alkynyl groups can be mono- or poly-unsaturated, so that alkyl, alkenyl and alkynyl chains having one or more double or triple bonds are also included. Alkenyl is, for example, vinyl, allyl, isobuten-3-yl, CH₂═CH—CH₂—CH═CH—, CH₂═CH—CH₂—CH₂—CH═CH— or CH₃—CH═CH—CH₂—CH═CH—. A preferred alkynyl is, for example, propargyl, and a preferred allenyl is CH₂═C═CH₂—.

An alkylene chain can also be substituted by one or more C₁-C₃alkyl groups, especially by methyl groups. Such alkylene chains and alkylene groups are preferably unsubstituted. The same applies also to all groups containing C₃-C₆cycloalkyl, C₃-C₅oxacycloalkyl, C₃-C₅thiacycloalkyl, C₃-C₄dioxacycloalkyl, C₃-C₄dithiacycloalkyl or C₃-C₄oxathiacycloalkyl which occur, for example, also as part of oxygen- and sulfur-containing heterocyclic ring systems of the radicals Ra₁ and Ra₂.

A C₁-C₄alkylene, C₁-C₄alkenylene or C₂-C₄alkynylene chain which may be interrupted by oxygen, —N(C₁-C₄alkyl)-, sulfur, sulfinyl or sulfonyl, or in X₂ or X₆ in the meaning of a C₁-C₆alkylene, C₃-C₆alkenylene or C₃-C₆alkynylene chain which can be mono- or poly-substituted by halogen or by X₄ or X₈, and wherein the unsaturated bonds of the chain are not bonded directly to the substituent X₁ or X₅, is to be understood as being, for example, —H₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, —CH₂CH₂CH₂CH₂—, —CH(CH₃)—, —CH₂CH(CH₃)—, —CH₂CH(CH₃)CH₂—, —CH₂CH(Cl)CH₂—, —CH₂CH(OCH₃)CH₂—, —CH₂O—, —OCH₂—, —CH₂OCH₂—, —OCH₂CH₂—, —OCH₂CH₂CH₂—, —CH₂OCH₂CH₂—, —CH₂OCH(CH₃)CH₂—, —SCH₂—, —SCH₂CH₂—, —SCH₂CH₂CH₂—, —CH₂S—, —CH₂SCH₂—, —CH₂S(O)CH₂—, —CH₂SO₂CH₂—, —CH₂SCH₂CH₂—, —CH₂S(O)CH₂CH₂—, —CH₂SO₂CH₂CH₂—, —CH₂SO₂NH—, —CH₂N(CH₃)SO₂CH₂CH₂—, —N(SO₂Me)CH₂CH₂—, —CH₂C(O)NH— or —CH₂NHC(O)CH₂—. A C₂-C₄alkenylene chain which may be uninterrupted or interrupted by oxygen is accordingly to be understood as being, for example, —CH═CH—CH₂—, —CH═CH—CH₂CH₂— or —CH═CHCH₂OCH₂—, and a C₂-C₄alkynylene chain which may be uninterrupted or interrupted by oxygen is to be understood as being, for example, —C≡C—, —C≡CCH₂—, —C≡CCH₂O—, —C≡CCH₂OCH₂— or —OC≡CCH₂—.

A three- to ten-membered mono- or bi-cyclic ring system Ra₁ or Ra₂, which may be interrupted once or up to three times selected from oxygen, sulfur, S(O), SO₂, N(Ra₆), carbonyl and C(═NORa₇) and which is bonded to the carbon atom of the substituent A₁ or to the group Q₁ or Q₂ either directly or by way of a C₁-C₄alkylene, C₁-C₄alkenylene or C₂-C₄alkynylene bridge which may be interrupted by oxygen, —N(C₁-C₄alkyl)-, sulfur, sulfinyl or sulfonyl, is to be understood as being, for example, 1-methyl-1H-pyrazol-3-yl, 1-ethyl-1H-pyrazol-3-yl, 1-propyl-1H-pyrazol-3-yl, 1H-pyrazol-3-yl, 1,5-dimethyl-1H-pyrazol-3-yl, 4-chloro-1-methyl-1H-pyrazol-3-yl, 1H-pyrazol-1-yl, 3-methyl-1H-pyrazol-1-yl, 3,5-dimethyl-1H-pyrazol-1-yl, 3-isoxazolyl, 5-methyl-3-isoxazolyl, 3-methyl-5-isoxazolyl, 5-isoxazolyl, 1H-pyrrol-2-yl, 1-methyl-1H-pyrrol-2-yl, 1H-pyrrol-1-yl, 1-methyl-1H-pyrrol-3-yl, 2-furanyl, 5-methyl-2-furanyl, 3-furanyl, 5-methyl-2-thienyl, 2-thienyl, 3-thienyl, 1-methyl-1H-imidazol-2-yl, 1H-imidazol-2-yl, 1-methyl-1H-imidazol-4-yl, 1-methyl-1H-imidazol-5-yl, 4-methyl-2-oxazolyl, 5-methyl-2-oxazolyl, 2-oxazolyl, 2-methyl-5-oxazolyl, 2-methyl-4-oxazolyl, 4-methyl-2-thiazolyl, 5-methyl-2-thiazolyl, 2-thiazolyl, 2-methyl-5-thiazolyl, 2-methyl-4-thiazolyl, 3-methyl-4-isothiazolyl, 3-methyl-5-isothiazolyl, 5-methyl-3-isothiazolyl, 1-methyl-1H-1,2,3-triazol-4-yl, 2-methyl-2H-1,2,3-triazol-4-yl, 4-methyl-2H-1,2,3-triazol-2-yl, 1-methyl-1H-1,2,4-triazol-3-yl, 1,5-dimethyl-1H-1,2,4-triazol-3-yl, 3-methyl-1H-1,2,4-triazol-1-yl, 5-methyl-1H-1,2,4-triazol-1-yl, 4,5-dimethyl-4H-1,2,4-triazol-3-yl, 4-methyl-4H-1,2,4-triazol-3-yl, 4H-1,2,4-triazol-4-yl, 5-methyl-1,2,3-oxadiazol-4-yl, 1,2,3-oxadiazol-4-yl, 3-methyl-1,2,4-oxadiazol-5-yl, 5-methyl-1,2,4-oxadiazol-3-yl, 4-methyl-3-furazanyl, 3-furazanyl, 5-methyl-1,2,4-oxadiazol-2-yl, 5-methyl-1,2,3-thiadiazol-4-yl, 1,2,3-thiadiazol-4-yl, 3-methyl-1,2,4-thiadiazol-5-yl, 5-methyl-1,2,4-thiadiazol-3-yl, 4-methyl-1,2,5-thiadiazol-3-yl, 5-methyl-1,3,4-thiadiazol-2-yl, 1-methyl-1H-tetrazol-5-yl, 1H-tetrazol-5-yl, 5-methyl-1H-tetrazol-1-yl, 2-methyl-2H-tetrazol-5-yl, 2-ethyl-2H-tetrazol-5-yl, 5-methyl-2H-tetrazol-2-yl, 2H-tetrazol-2-yl, 2-pyridinyl, 6-methyl-2-pyridinyl, 4-pyridinyl, 3-pyridinyl, 6-methyl-3-pyridazinyl, 5-methyl-3-pyridazinyl, 3-pyridazinyl, 4,6-dimethyl-2-pyrimidinyl, 4-methyl-2-pyrimidinyl, 2-pyrimidinyl, 2-methyl-4-pyrimidinyl, 2-chloro-4-pyrimidinyl, 2,6-dimethyl-4-pyrimidinyl, 4-pyrimidinyl, 2-methyl-5-pyrimidinyl, 6-methyl-2-pyrazinyl, 2-pyrazinyl, 4,6-dimethyl-1,3,5-triazin-2-yl, 4,6-dichloro-1,3,5-triazin-2-yl, 1,3,5-triazin-2-yl, 4methyl-1,3,5-triazin-2-yl, 3-methyl-1,2,4-triazin-5-yl, 3-methyl-1,2,4-triazin-6-yl,

wherein each R₂₆ is methyl, each R₂₇ independently is hydrogen, C₁-C₃alkyl, C₁-C₃alkoxy, C₁-C₃alkylthio or trifluoromethyl, and X₉ is oxygen or sulfur.

A further annellated (fused-on), monocyclic or bicyclic ring system which is formed, for example, by two adjacent substituents Ra₁ and Ra₂ or Ra₁ and Ra₅ and which is uninterrupted or interrupted once or up to three times selected from oxygen, sulfur, S(O), SO₂, —N(Ra₆)—, carbonyl and C(═NORa₇) and which may be additionally substituted by one or more substituents is to be understood as being, for example, an annellated, bidentate ring system of formula

wherein especially R₄₆ is hydrogen, halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄alkylthio; R₄₇ is hydrogen, halogen, C₁-C₄alkyl or C₁-C₄alkoxy; and R₅₀, R₅₁, R₅₂, R₅₃, R₅₄, R₅₅, R₅₆, R₅₇, R₅₈ and R₅₉ are hydrogen or C₁-C₄alkyl; and X₁₀ is oxygen or NOR₅₉.

HPPD Inhibitors of formula I are described, for example, in WO/0015615, WO 00/37437, WO 01/66522 and WO 01/94339.

Compounds of formula I that are well suited to the method according to the invention are those wherein

-   T is T₁; -   R₁ and R₂ are hydrogen; -   A is C₁-C₂alkylene; -   D and E together are C₂-C₃alkylene; -   Q is Q₁, wherein -   A₁ is methine, CRa₁ or ═N—(O)_(p), but preferably ═N—(O)_(p); -   p is 0; -   Ra₁ is hydrogen, C₁-C₆alkyl, hydroxy, C₁-C₆alkoxy, C₁-C₆haloalkoxy,     C₃-C₆alkenyloxy, C₃-C₆haloalkenyloxy, C₃-C₆alkynyloxy,     C₁-C₄alkylcarbonyloxy, C₁-C₄alkylsulfonyloxy, tosyloxy,     C₁-C₄alkylthio, C₁-C₄alkylsulfinyl, C₁-C₄alkylsulfonyl,     C₁-C₄alkylamino, C₁-C₄dialkylamino, C₁-C₄alkoxycarbonyl,     C₁-C₄haloalkyl, formyl, cyano, halogen, phenyl or phenoxy; it being     possible for phenyl in turn to be substituted by C₁-C₃alkyl,     C₁-C₃haloalkyl, C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by     nitro; -   Ra₂ is hydrogen, C₁-C₆alkyl, C₁-C₆haloalkyl, C₂-C₆alkenyl,     C₂-C₆haloalkenyl, vinyl substituted by C₁-C₂alkoxycarbonyl or by     phenyl, C₂-C₆alkynyl, C₂-C₆haloalkynyl, ethynyl substituted by     trimethylsilyl, hydroxy, C₁-C₂alkoxy, C₁-C₂alkoxycarbonyl or by     phenyl, C₃-C₆allenyl, C₃-C₆cycloalkyl, halo-substituted     C₃-C₆cycloalkyl, C₁-C₆alkoxy, C₃-C₆alkenyloxy, C₃-C₆alkynyloxy,     C₁-C₆haloalkoxy, C₃-C₆haloalkenyloxy, cyano-C₁-C₄alkoxy,     C₁-C₄alkoxy-C₁-C₄alkoxy, C₁-C₄alkylthio-C₁-C₄alkoxy,     C₁-C₄alkylsulfinyl-C₁-C₄alkoxy, C₁-C₄alkylsulfonyl-C₁-C₄alkoxy,     C₁-C₄alkoxycarbonyl-C₁-C₄alkoxy, C₁-C₆alkylthio, C₁-C₆alkylsulfinyl,     C₁-C₆alkylsulfonyl, C₁-C₆haloalkylthio, C₁-C₆haloalkylsulfinyl,     C₁-C₆haloalkylsulfonyl, C₁-C₄alkoxycarbonyl-C₁-C₄alkylthio,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfinyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkylsulfonyl, benzyl-S—, benzyl-SO—,     benzyl-SO₂—, C₁-C₆alkylamino, C₂-C₆dialkylamino,     C₁-C₆alkylaminosulfonyl, di(C₁-C₆alkylamino)sulfonyl, benzyloxy,     benzyl, phenyl, phenoxy, phenylthio, phenylsulfinyl or     phenylsulfonyl, it being possible for the phenyl-containing groups     in turn to be substituted by C₁-C₃alkyl, C₁-C₃haloalkyl,     C₁-C₃alkoxy, C₁-C₃haloalkoxy, halogen, cyano or by nitro, or Ra₂ is     OS—C₁-C₄alkyl, OSO—C₁-C₄alkyl, OSO₂—C₁-C₄alkyl, OS—C₁-C₄haloalkyl,     OSO—C₁-C₄haloalkyl, OSO₂—C₁-C₄haloalkyl, N(C₁-C₄alkyl)-S—C₁-C₄alkyl,     N(C₁-C₄alkyl)-SO—C₁-C₄alkyl, N(C₁-C₄alkyl)-SO₂—C₁-C₄alkyl, cyano,     carbamoyl, C₁-C₄alkoxycarbonyl, formyl, halogen, rhodano, amino,     hydroxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkyl-S—C₁-C₄alkyl,     C₁-C₄alkyl-SO—C₁-C₄alkyl, C₁-C₄alkyl-SO₂—C₁-C₄alkyl,     cyano-C₁-C₄alkyl, C₁-C₆alkylcarbonyloxy-C₁-C₄alkyl,     C₁-C₄alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄alkoxycarbonyloxy-C₁-C₄alkyl,     C₁-C₄rhodano-C₁-C₄alkyl, benzoyloxy-C₁-C₄alkyl, C₂-C₆oxiranyl,     C₁-C₄alkylamino-C₁-C₄alkyl, di(C₁-C₄alkyl)amino-C₁-C₄alkyl,     C₁-C₁₂alkylthiocarbonyl-C₁-C₄alkyl or formyl-C₁-C₄alkyl, or Ra₂ is     the group —X₁-X₃ or the group —X₂-X₁-X₃; wherein X₁, X₂ and X₃ are     as defined above; -   Ra₃ and Ra₄ are hydrogen and Ra₅ is as defined above.

Compounds of formula I that are especially well suited to the method according to the invention are those wherein

-   T is T₁; -   R₁ and R₂ are hydrogen, A is methylene, D and E together are     ethylene, A₁ is ═N—(O)_(p); -   wherein p is 0; -   Q is Q₁, Ra₃ and Ra₄ are hydrogen, Ra₅ is C₁-C₃haloalkyl, especially     trifluoromethyl, and Ra₂ is C₁-C₄alkoxy-C₁-C₄alkoxy-C₁-C₄alkyl,     especially methoxyethoxymethyl.

Further compounds of formula I that are especially well suited to the method according to the invention are listed in the following Tables:

In the Tables, CCH is the ethynyl group, Ph is the phenyl group and Me is the methyl group.

TABLE 1 Compounds of formula Ie (Ie)

Comp. No. Ra₂ Ra₅ Ra₄ Ra₃ p 1.001 H CF₃ H H 0 1.002 F CF₃ H H 0 1.003 Cl CF₃ H H 0 1.004 Br CF₃ H H 0 1.005 CHF₂ CF₃ H H 0 1.006 CCl₃ CF₃ H H 0 1.007 CCIF₂ CF₃ H H 0 1.008 CH₃ CF₃ H H 0 1.009 CH₃ CF₃ H H 0 1.01 CH₂CH₃ CF₃ H H 0 1.011 CH(CH₃)₂ CF₃ H H 0 1.012 (CH₂)₂CH₃ CF₃ H H 0 1.013 C(CH₃)₃ CF₃ H H 0 1.014 Ph CF₃ H H 0 1.015 CH₂F CF₃ H H 0 1.016 CH₂Cl CF₃ H H 0 1.017 CH₂Br CF₃ H H 0 1.018 CH₂OH CF₃ H H 0 1.019 CH₂OCOCH₃ CF₃ H H 0 1.02 CH₂OCOPh CF₃ H H 0 1.021 CH₂OCH₃ CF₃ H H 0 1.022 CH₂OCH₂CH₃ CF₃ H H 0 1.023 CH₂CH₂OCH₃ CF₃ H H 0 1.024 CH₂SMe CF₃ H H 0 1.025 CH₂SOMe CF₃ H H 0 1.026 CH₂SO₂Me CF₃ H H 0 1.027 CH₂SO₂Ph CF₃ H H 0 1.028 SCH₂Ph CF₃ H H 0 1.029 SOCH₂Ph CF₃ H H 0 1.03 SO₂CH₂Ph CF₃ H H 0 1.031 SCH₃ CF₃ H H 0 1.032 SOCH₃ CF₃ H H 0 1.033 SO₂CH₃ CF₃ H H 0 1.034 SPh CF₃ H H 0 1.035 SOPh CF₃ H H 0 1.036 SO₂Ph CF₃ H H 0 1.037 N(CH₃)₂ CF₃ H H 0 1.038 CH═CH₂ CF₃ H H 0 1.039 CH₂CH═CH₂ CF₃ H H 0 1.04 SO₂N(CH₃)₂ CF₃ H H 0 1.041 Ethynyl CF₃ H H 0 1.042 Cyclopropyl CF₃ H H 0 1.043 OCH₃ CF₃ H H 0 1.044 OPh CF₃ H H 0 1.045 OCHF_(2 CF) ₃ H H 0 1.046 CO₂Me CF₃ H H 0 1.047 2-Furyl CF₃ H H 0 1.048 OCH₂ethynyl CF₃ H H 0 1.049 2-Pyridyl CF₃ H H 0 1.05 3-Pyridyl CF₃ H H 0 1.051 4-Pyridyl CF₃ H H 0 1.052 H CF₃ H H 1 1.053 F CF₃ H H 1 1.054 Cl CF₃ H H 1 1.055 Br CF₃ H H 1 1.056 CHF₂ CF₃ H H 1 1.057 CCl₃ CF₃ H H 1 1.058 CClF₂ CF₃ H H 1 1.059 CF₃ CF₃ H H 1 1.06 CH3 CF₃ H H 1 1.061 CH₂CH₃ CF₃ H H 1 1.062 CH(CH₃)₂ CF₃ H H 1 1.063 (CH₂)₂CH₃ CF₃ H H 1 1.064 C(CH₃)₃ CF₃ H H 1 1.065 Ph CF₃ H H 1 1.066 CH₂F CF₃ H H 1 1.067 CH₂Cl CF₃ H H 1 1.068 CH₂Br CF₃ H H 1 1.069 CH₂OH CF₃ H H 1 1.07 CH₂OCOCH₃ CF₃ H H 1 1.071 CH₂OCOPh CF₃ H H 1 1.072 CH₂OCH₃ CF₃ H H 1 1.073 CH₂OCH₂CH₃ CF₃ H H 1 1.074 CH₂CH₂OCH₃ CF₃ H H 1 1.075 CH₂SMe CF₃ H H 1 1.076 CH₂SOMe CF₃ H H 1 1.077 CH₂SO₂Me CF₃ H H 1 1.078 CH₂SO₂Ph CF₃ H H 1 1.079 SCH₂Ph CF₃ H H 1 1.08 SOCH₂Ph CF₃ H H 1 1.081 SO₂CH₂Ph CF₃ H H 1 1.082 SCH₃ CF₃ H H 1 1.083 SOCH₃ CF₃ H H 1 1.084 SO₂CH₃ CF₃ H H 1 1.085 SPh CF₃ H H 1 1.086 SOPh CF₃ H H 1 1.087 SO₂Ph CF₃ H H 1 1.088 N(CH₃)₂ CF₃ H H 1 1.089 CH═CH₂ CF₃ H H 1 1.09 CH₂CH═CH₂ CF₃ H H 1 1.091 SO₂N(CH₃)₂ CF₃ H H 1 1.092 Ethynyl CF₃ H H 1 1.093 Cyclopropyl CF₃ H H 1 1.094 OCH₃ CF₃ H H 1 1.095 OPh CF₃ H H 1 1.096 OCHF₂ CF₃ H H 1 1.097 CO₂Me CF₃ H H 1 1.098 2-Furyl CF₃ H H 1 1.099 OCH₂CCH CF₃ H H 1 1.1 2-Pyridyl CF₃ H H 1 1.101 3-Pyridyl CF₃ H H 1 1.102 4-Pyridyl CF₃ H H 1 1.103 H CF₂CF₃ H H 0 1.104 Cl CF₂CF₃ H H 0 1.105 CHF₂ CF₂CF₃ H H 0 1.106 CCl₃ CF₂CF₃ H H 0 1.107 CClF₂ CF₂CF₃ H H 0 1.108 CF₃ CF₂CF₃ H H 0 1.109 CH₃ CF₂CF₃ H H 0 1.11 CH₂CH₃ CF₂CF₃ H H 0 1.111 CH(CH₃)₂ CF₂CF₃ H H 0 1.112 (CH₂)₂CH₃ CF₂CF₃ H H 0 1.113 C(CH₃)₃ CF₂CF₃ H H 0 1.114 CH₂F CF₂CF₃ H H 0 1.115 CH₂Cl CF₂CF₃ H H 0 1.116 CH₂OH CF₂CF₃ H H 0 1.117 CH₂OCOCH₃ CF₂CF₃ H H 0 1.118 CH₂OCOPh CF₂CF₃ H H 0 1.119 CH₂OCH₃ CF₂CF₃ H H 0 1.12 CH₂OCH₂CH₃ CF₂CF₃ H H 0 1.121 CH₂SMe CF₂CF₃ H H 0 1.122 CH₂SOMe CF₂CF₃ H H 0 1.123 CH₂SO₂Me CF₂CF₃ H H 0 1.124 CH₂SO₂Ph CF₂CF₃ H H 0 1.125 N(CH₃)₂ CF₂CF₃ H H 0 1.126 CH═CH₂ CF₂CF₃ H H 0 1.127 CH₂CH═CH₂ CF₂CF₃ H H 0 1.128 SO₂N(CH₃)₂ CF₂CF₃ H H 0 1.129 CCH CF₂CF₃ H H 0 1.13 Cyclopropyl CF₂CF₃ H H 0 1.131 OPh CF₂CF₃ H H 0 1.132 OCH₃ CF₂CF₃ H H 0 1.133 CO₂Me CF₂CF₃ H H 0 1.134 OCH₂CCH CF₂CF₃ H H 0 1.135 2-Pyridyl CF₂CF₃ H H 0 1.136 3-Pyridyl CF₂CF₃ H H 0 1.137 4-Pyridyl CF₂CF₃ H H 0 1.138 H CF₂CF₃ H H 1 1.139 Cl CF₂CF₃ H H 1 1.14 CHF₂ CF₂CF₃ H H 1 1.141 CCl₃ CF₂CF₃ H H 1 1.142 CCIF₂ CF₂CF₃ H H 1 1.143 CF₃ CF₂CF₃ H H 1 1.144 CH₃ CF₂CF₃ H H 1 1.145 CH₂CH₃ CF₂CF₃ H H 1 1.146 CH(CH₃)₂ CF₂CF₃ H H 1 1.147 (CH₂)₂CH₃ CF₂CF₃ H H 1 1.148 C(CH₃)₃ CF₂CF₃ H H 1 1.149 CH₂F CF₂CF₃ H H 1 1.15 CH₂Cl CF₂CF₃ H H 1 1.151 CH₂OH CF₂CF₃ H H 1 1.152 CH₂OCOCH₃ CF₂CF₃ H H 1 1.153 CH₂OCOPh CF₂CF₃ H H 1 1.154 CH₂OCH₃ CF₂CF₃ H H 1 1.155 CH₂OCH₂CH₃ CF₂CF₃ H H 1 1.156 CH₂SMe CF₂CF₃ H H 1 1.157 CH₂SOMe CF₂CF₃ H H 1 1.158 CH₂SO₂Me CF₂CF₃ H H 1 1.159 CH₂SO₂Ph CF₂CF₃ H H 1 1.16 N(CH3)2 CF2CF₃ H H 1 1.161 CH═CH₂ CF₂CF₃ H H 1 1.162 CH₂CH═CH₂ CF₂CF₃ H H 1 1.163 SO₂N(CH₃)₂ CF₂CF₃ H H 1 1.164 CCH CF₂CF₃ H H 1 1.165 Cyclopropyl CF₂CF₃ H H 1 1.166 OPh CF₂CF₃ H H 1 1.167 OCH₃ CF₂CF₃ H H 1 1.168 CO₂Me CF₂CF₃ H H 1 1.169 OCH₂CCH CF₂CF₃ H H 1 1.17 2-Pyridyl CF₂CF₃ H H 1 1.171 3-Pyridyl CF₂CF₃ H H 1 1.172 4-Pyridyl CF₂CF₃ H H 1 1.173 H CF₂CF₂CF₃ H H 0 1.174 CHF₂ CF₂CF₂CF₃ H H 0 1.175 CF₃ CF₂CF₂CF₃ H H 0 1.176 CH₃ CF₂CF₂CF₃ H H 0 1.177 CH₂CH₃ CF₂CF₂CF₃ H H 0 1.178 (CH₂)₂CH₃ CF₂CF₂CF₃ H H 0 1.179 CH2Cl CF₂CF₂CF₃ H H 0 1.18 CH₂OCH₃ CF₂CF₂CF₃ H H 0 1.181 H CF₂CF₂CF₃ H H 1 1.182 CHF₂ CF₂CF₂CF₃ H H 1 1.183 CF₃ CF₂CF₂CF₃ H H 1 1.184 CH₃ CF₂CF₂CF₃ H H 1 1.185 CH₂CH₃ CF₂CF₂CF₃ H H I 1.186 (CH₂)₂CH₃ CF₂CF₂CF₃ H H 0 1.187 CH₂Cl CF₂CF₂CF₃ H H 1 1.188 CH₂OCH₃ CF₂CF₂CF₃ H H 1 1.189 H CF₂Cl H H 0 1.19 Cl CF₂Cl H H 0 1.191 CHF₂ CF₂Cl H H 0 1.192 CCl₃ CF₂Cl H H 0 1.193 CCIF₂ CF₂Cl H H 0 1.194 CF₃ CF₂Cl H H 0 1.195 CH₃ CF₂Cl H H 0 1.196 CH₂CH₃ CF₂Cl H H 0 1.197 CH(CH₃)₂ CF₂Cl H H 0 1.198 (CH₂)₂CH₃ CF₂Cl H H 0 1.199 C(CH₃)₃ CF₂Cl H H 0 1.2 CH₂F CF₂Cl H H 0 1.201 CH₂Cl CF₂Cl H H 0 1.202 CH₂OH CF₂Cl H H 0 1.203 CH₂OCOCH₃ CF₂Cl H H 0 1.204 CH₂OCOPh CF₂Cl H H 0 1.205 CH₂OCH₃ CF₂Cl H H 0 1.206 CH₂OCH₂CH₃ CF₂Cl H H 0 1.207 CH₂SMe CF₂Cl H H 0 1.208 CH₂SOMe CF₂Cl H H 0 1.209 CH₂SO₂Me CF₂Cl H H 0 1.21 CH₂SO₂Ph CF₂Cl H H 0 1.211 N(CH₃)₂ CF₂Cl H H 0 1.212 CH═CH₂ CF₂Cl H H 0 1.213 CH₂CH═CH₂ CF₂Cl H H 0 1.214 SO₂N(CH₃)₂ CF₂Cl H H 0 1.215 CCH CF₂Cl H H 0 1.216 Cyclopropyl CF₂Cl H H 0 1.217 OPh CF₂Cl H H 0 1.218 OCH₃ CF₂Cl H H 0 1.219 CO₂Me CF₂Cl H H 0 1.22 OCH₂CCH CF₂Cl H H 0 1.221 2-Pyridyl CF₂Cl H H 0 1.222 3-Pyridyl CF₂Cl H H 0 1.223 4-Pyridyl CF₂Cl H H 0 1.224 H CF₂Cl H H 1 1.225 Cl CF₂Cl H H 1 1.226 CHF₂ CF₂Cl H H 1 1.227 CCl₃ CF₂Cl H H 1 1.228 CCIF₂ CF₂Cl H H 1 1.229 CF₃ CF₂Cl H H 1 1.23 CH₃ CF₂Cl H H 1 1.231 CH₂CH₃ CF₂Cl H H 1 1.232 CH(CH₃)₂ CF₂Cl H H 1 1.233 (CH₂)₂CH₃ CF₂Cl H H 1 1.234 C(CH₃)₃ CF₂Cl H H 1 1.235 CH₂F CF₂Cl H H 1 1.236 CH₂Cl CF₂Cl H H 1 1.237 CH₂OH CF₂Cl H H 1 1.238 CH₂OCOCH₃ CF₂Cl H H 1 1.239 CH₂OCOPh CF₂Cl H H 1 1.24 CH₂OCH₃ CF₂Cl H H 1 1.241 CH₂OCH₂CH₃ CF₂Cl H H 1 1.242 CH₂SMe CF₂Cl H H 1 1.243 CH₂SOMe CF₂Cl H H 1 1.244 CH₂SO₂Me CF₂Cl H H 1 1.245 CH₂SO₂Ph CF₂Cl H H 1 1.246 N(CH₃)₂ CF₂Cl H H 1 1.247 CH═CH₂ CF₂Cl H H 1 1.248 CH₂CH═CH₂ CF₂Cl H H 1 1.249 SO₂N(CH₃)₂ CF₂Cl H H 1 1.25 CCH CF₂Cl H H 1 1.251 Cyclopropyl CF₂Cl H H 1 1.252 OPh CF₂Cl H H 1 1.253 OCH₃ CF₂Cl H H 1 1.254 CO₂Me CF₂Cl H H 1 1.255 OCH₂CCH CF₂Cl H H 1 1.256 H CCl₃ H H 0 1.257 Cl CCl₃ H H 0 1.258 CH₃ CCl₃ H H 0 1.259 CH₂CH₃ CCl₃ H H 0 1.26 CH(CH₃)₂ CCl₃ H H 0 1.261 (CH₂)₂CH₃ CCl₃ H H 0 1.262 CH₂F CCl₃ H H 0 1.263 CH₂Cl CCl₃ H H 0 1.264 CH₂OH CCL₃ H H 0 1.265 CH₂OCOCH₃ CCl₃ H H 0 1.266 CH₂OCOPh CCl₃ H H 0 1.267 CH₂OCH₃ CCl₃ H H 0 1.268 CH₂OCH₂CH₃ CCl₃ H H 0 1.269 CH₂SMe CCl₃ H H 0 1.27 CH₂SOMe CCl₃ H H 0 1.271 CH₂SO₂Me CCl₃ H H 0 1.272 CH₂SO₂Ph CCl₃ H H 0 1.273 Cyclopropyl CCl₃ H H 0 1.274 OPh CCl₃ H H 0 1.275 OCH₃ CCl₃ H H 0 1.276 CO₂Me CCl₃ H H 0 1.277 OCH₂CCH CCl₃ H H 0 1.278 H CCl₃ H H 1 1.279 Cl CCl₃ H H 1 1.28 CH₃ CCl₃ H H 1 1.281 CH₂CH₃ CCl₃ H H 1 1.282 CH(CH₃)₂ CCl₃ H H 1 1.283 (CH₂)₂CH₃ CCl₃ H H 1 1.284 CH₂F CCl₃ H H 1 1.285 CH₂Cl CCl₃ H H 1 1.286 CH₂OH CCl₃ H H 1 1.287 CH₂OCOCH₃ CCl₃ H H 1 1.288 CH₂OCOPh CCl₃ H H 1 1.289 CH₂OCH₃ CCl₃ H H 1 1.29 CH₂OCH₂CH₃ CCl₃ H H 1 1.291 CH₂SMe CCl₃ H H 1 1.292 CH₂SOMe CCl₃ H H 1 1.293 CH₂SO₂Me CCl₃ H H 1 1.294 CH₂SO₂Ph CCl₃ H H 1 1.295 Cyclopropyl CCl₃ H H 1 1.296 OPh CCl₃ H H 1 1.297 OCH₃ CCl₃ H H 1 1.298 CO₂Me CCl₃ H H 1 1.299 OCH₂CCH CCl₃ H H 1 1.3 CF₃ CHF2 H H 0 1.301 CH₃ CHF₂ H H 0 1.302 CH₂OCH₃ CHF₂ H H 0 1.303 CH₂Cl CHF₂ H H 0 1.304 CH₂F CHF₂ H H 0 1.305 CF₃ CHF₂ H H 1 1.306 CH₃ CHF₂ H H 1 1.307 CH₂OCH3 CHF₂ H H 1 1.308 CH₂Cl CHF₂ H H 1 1.309 CH₂F CHF₂ H H 1 1.31 CH₃ CF₃ H CH₃ 0 1.311 CH₃ CF₃ H CH₃ 1 1.312 Cl CF₃ H CH₃ 0 1.313 CH₃ CF₃ CH₃ H 0 1.314 CH₃ CF₃ Ph H 0 1.315 CH₃ CF₃ Cl H 0 1.316 CH₃ CF₃ CO₂CH₂CH₃ H 0 1.317 CH₃ CF₃ CO₂CH₂Ph H 0 1.318 CH₃ CF₃ CH₃ H 1 1.319 CH₃ CF₃ Ph H 1 1.32 CH₃ CF₃ Cl H 1 1.321 CH₃ CF₃ CO₂CH₂CH₃ H 1 1.322 CH₃ CF₃ CO₂CH₂Ph H 1 1.323 OCH₃ CF₃ CH₃ H 0 1.324 CH₂OCH₃ CF₃ CH₃ H 0 1.325 CH₂OCH₃ CF₃ Ph H 0 1.326 CH₂OCH₃ CF₃ Cl H 0 1.327 CH₂OCH₃ CF₃ CO₂CH₂CH₃ H 0 1.328 CH₂OCH₃ CF₃ CO₂CH₂Ph H 0 1.329 CH₂OCH₃ CF₃ CH₃ H 1 1.33 CH₂OCH₃ CF₃ Ph H 1 1.331 CH₂OCH₃ CF₃ Cl H 1 1.332 CH₂OCH₃ CF₃ CO₂CH₂CH₃ H 1 1.333 CH₂OCH₃ CF₃ CO₂CH₂Ph H 1 1.334 COOCH₃ H H H 0 1.335 CF₃ SCH₃ H H 0 1.336 CH₃ SCH₃ H H 0 1.337 CF₃ SOCH₃ H H 0 1.338 CH₃ SOCH₃ H H 0 1.339 CF₃ SO₂CH₃ H H 0 1.34 CH₃ SO₂CH₃ H H 0 1.341 CF₃ SCH₂CH₃ H H 0 1.342 CH₃ SCH₂CH₃ H H 0 1.343 CF₃ SOCH₂CH₃ H H 0 1.344 CH₃ SOCH₂CH₃ H H 0 1.345 CF₃ SO₂CH₂CH₃ H H 0 1.346 CH₃ SO₂CH₂CH₃ H H 0 1.347 CF₃ OCH₃ H H 0 1.348 CH₃ OCH₃ H H 0 1.349 CF₃ OCH₂CF₃ H H 0 1.35 CH₃ OCH₂CF₃ H H 0 1.351 CF₃ OCH₂CCH H H 0 1.352 CH₃ OCH₂CCH H H 0 1.353 CF₃ CN H H 0 1.354 CH₃ CN H H 0 1.355 CF₃ Cl H H 0 1.356 CF₃ Cl H H 0 1.357 CH₃ Cl H H 0 1.358 H Cl H H 0 1.359 CF₃ OCH₃ H H 0 1.36 CH₃ OCH₃ H H 0 1.361 CF₃ CH₃ H H 0 1.362 H CF₃ H CH₃ 0 1.363 H CF₃ H CF₃ 0 1.364 H CF₃ H CH₂CH₃ 0 1.365 H CF₃ H CF₃ 0 1.366 H CF₃ H SCH₃ 0 1.367 H CF₃ H SOCH₃ 0 1.368 H CF₃ H SO₂CH₃ 0 1.369 H CF₃ H Cl 0 1.37 H CF₃ H OCH₃ 0 1.371 H CH₃ H CF₃ 0 1.372 H Cl H CF₃ 0 1.373 H OCH₃ H CF₃ 0 1.374 H SCH₃ H CF₃ 0 1.375 H SOCH₃ H CF₃ 0 1.376 CF₂H SOCH₂CH₃ H H 0 1.377 CF₂Cl SOCH₂CH₃ H H 0 1.378 CF₂H SO₂CH₂CH₃ H H 0 1.379 CF₂Cl SO₂CH₂CH₃ H H 0 1.38 CF₂H OCH₃ H H 0 1.381 CF₂Cl OCH₃ H H 0 1.382 CF₂H OCH₂CF₃ H H 0 1.383 CF₂Cl OCH₂CF₃ H H 0 1.384 CF₂H OCH₂CCH H H 0 1.385 CF₂Cl OCH₂CCH H H 0 1.386 CF₂H CN H H 0 1.387 CF₂Cl CN H H 0 1.388 CF₂H Cl H H 0 1.389 CF₂Cl Cl H H 0 1.39 CF₂H OCH₃ H H 0 1.391 CF₂Cl OCH₃ H H 0 1.392 CF₃ CH₂OCH₃ H H 0 1.393 CF₃ CH₂OCH₃ H H 1 1.394 CF₂Cl CH₂OCH₃ H H 0 1.395 CF₂Cl CH₂OCH₃ H H 1 1.396 CF_(2H) CH₂OCH₃ H H 0 1.397 CF_(2H) CH₂OCH₃ H H 1 1.398 CN CF₃ H H 0

TABLE 2 Preferred HPPD inhibitors accordincg to the present invention: Comp. No. Structure: 2.01

2.02

2.03

2.04

2.05

2.06

2.07

2.08

2.09

2.10

2.11

2.12

2.13

2.14

2.15

2.16

2.17

2.18

2.19

The compounds 2.04, 2.10 and 2.13 are especially preferred. Compound No. 2.01 is known from The Pesticide Manual 12^(th) ed., Entry No.: 467. Compound No. 2.02 (4-chloro-2-mesylphenyl-5-cyclopropyl-1,2-oxazol-4-yl ketone) is registered under Chemical Abstracts No. 141112-06-3. Compound No. 2.03 is known from The Pesticide Manual 12^(th) ed., Entry No.: 710, and compound No. 2.04 is described under Entry No. 500. Compound No. 2.05 is known from The Pesticide Manual 12^(th) ed., under Entry No.: 71; compound No. 2.06 under Entry No. 663; compound No. 2.07 under Entry No. 666; and compound No. 2.08 under Entry No. 70. Compounds No. 2.09 and 2.10 are described in WO 98/31681, and mixtures of those compounds with herbicides are known from WO 99/65314. Compound No. 2.11 is described in Chemical Abstracts under the registration number CAS 192708-91-1.

Compound No. 2.12 is described in WO 98/42677 A1 and U.S. Pat. No. 6,211,403 B1 and has the Chemical Abstracts registration number 128133-27-7. Compounds No. 2.13 and 2.14 and their preparation are known from WO/0015615. Compound 2.15 is described in EP-A-0 496 631, and compound 2.16 is described in WO 03/092380. Compound No. 2.17 is known from WO 02/085118, and compound No. 2.18 from WO 02/021924. Compound No. 2.19 is described in WO 04/021788. 

1. A method of labelling soya varieties as to their suitability as a subsequent crop to maize when weed control in that maize crop has been carried out using HPPD inhibitor herbicides, wherein: a) in a first step, a reference soya variety is selected which, when grown as a subsequent crop to maize wherein weed control has been carried out using HPPD inhibitor herbicides and wherein soil residues of the HPPD inhibitor herbicides exist at the time the soya variety is subsequently grown, exhibits from 5 to 20% phytotoxicity with respect to those HPPD inhibitor herbicide soil residues; b) in a second step, the phytotoxicity of soya varieties when grown in the same manner as the reference variety in the first step is determined in relation to that reference soya variety in the form of a factor; and c) in a third step, said soya varieties are labelled with said factor.
 2. A method according to claim 1, wherein the reference soya variety is a variety selected from NK S40-R9, Pioneer 94B01, NK S46-W8, Mustang M-222RR, AGI 7370 RR, Pioneer 9492, Pioneer 93B67, Pioneer 90B51, S. Grow SG948R and Pioneer 94B54.
 3. A method according to claim 1, wherein the HPPD inhibitor herbicide is a compound of formula Ie

wherein p is 0 or 1; Ra₂ is C₁-C₄alkoxy-C₁-C₄alkoxy-C₁-C₄alkyl; Ra₃ and Ra₄ are hydrogen; and Ra₅ is C₁-C₃haloalkyl. 